C. -2
For future reference, the periodic table should tell you.
A mole is the assemblage of 6.022×10^23 ions.This number is also known as Avogadro Number.
Avogadro constant=6.022×10^23 mol^-1
Answer:
A
Explanation:
In chemistry, a mixture is a material made up of two or more different substances which are not chemically combined. A mixture is the physical combination of two or more substances in which the identities are retained and are mixed in the form of solutions, suspensions, and colloids.
H₃O ions are when water is protonated
H₂O + H⁺ --> H₃O⁺
HCl is a strong acid therefore complete ionisation takes place.
HCl ---> H⁺ + Cl⁻
1 mol of HCl dissociates to give out 1 mol of H⁺
since H⁺ together with water forms H₃O⁺ ions,
[HCl] = [H₃O⁺]
therefore concentration of [H₃O⁺] is 0.0005 M